How to Make It
Preheat the oven to 350°. Arrange the pitas on a baking sheet, rough sides up, and spread each round with 1 tablespoon of the butter. Bake for about 8 minutes, until crisp. Let cool and break into large pieces.
Meanwhile, in a small bowl, steep the shallot in the vinegar for 5 minutes. Stir in the olive oil, then add the sour cream and garlic and season with salt and pepper.
In a large bowl, toss the endives with the anchovies and toasted pita. Add the sour cream dressing and toss well. Spoon onto 4 plates and serve.